High-value bio-oil rich in monocyclic aromatic hydrocarbons (MAHs) was produced via microwave-assisted ex-situ catalytic co-pyrolysis of eucalyptus wood (EW) and polypropylene (PP) over MFI nanosheet zeolite (MNZ). The effects of catalyst loading (0–200 wt%), catalytic temperature (450–650 °C), and microwave power (600–1400 W) on product yields, liquid-phase composition, and catalyst coke deposition were systematically investigated. Among the investigated conditions, the best overall performance was obtained at 100 wt% MNZ, a catalytic temperature of 500 °C, and a microwave power of 1000 W, yielding 53.5 wt% bio-oil with a relative MAHs content of 39.83 %. Under identical conditions, the relative MAHs content obtained with MNZ was 2.46 times that obtained with conventional HZSM-5, while reducing coke deposition from 2.51 to 1.23 wt%. The enhanced catalytic performance of MNZ was associated with its hierarchical pore architecture, greater mesoporous volume, and higher Brønsted/Lewis acid ratio, which improve the accessibility of acid sites and mass transport of reaction intermediates. Electromagnetic characterization further showed that, at 2.45 GHz, MNZ exhibited a higher dielectric loss tangent and attenuation constant than HZSM-5, consistent with its faster microwave-heating response. These results demonstrate the potential of MNZ for promoting MAHs formation and suppressing coke accumulation during microwave-assisted ex-situ catalytic co-pyrolysis of EW and PP within the investigated conditions.

To enhance the reactivity and cyclic stability of red mud-based oxygen carriers in biomass chemical looping gasification (BCLG), carbide slag was introduced to construct a Ca-Fe synergistically modified oxygen carrier, and its reaction behavior was systematically assessed. The results show that, compared with the pristine red mud (RM), the modified sample (R5C5) significantly improves the yield of hydrogen-rich syngas, achieving a maximum syngas yield of 543 mL mL/gbio and a 42.4% increase in H2 yield. During ten consecutive gasification cycles, R5C5 maintained a high average total gas yield of 815.4 mL/gbio and an average syngas yield of 493.4 mL/gbio, indicating superior cyclic stability. The Ca-based sorption phase promotes the water-gas shift reaction by lowering the CO2 partial pressure through in-situ CO2 capture. Meanwhile, the introduced basic sites adsorb and activate tar molecules, facilitating their further cracking into light gaseous products. The Ca-Fe synergistic effect not only enhances lattice oxygen mobility and oxygen transfer capacity but also suppresses the agglomeration of active phases through a physically cooperative interaction. This segregated Ca-Fe synergistic structure avoids the formation of chemically locked calcium ferrite phases that would otherwise hinder oxygen redox kinetics. Overall, this work advances the development of sorption-enhanced chemical looping gasification (SE-CLG) and provides a feasible strategy for the valorization of industrial solid waste in designing dual functional oxygen carriers.

Red mud (RM), an iron-based industrial solid waste, holds potential as an oxygen carriers (OCs) for biomass chemical looping gasification due to its low cost. To enhance the reactivity of red mud, this paper proposed a modification scheme involving co-doping with spent lithium-ion battery cathode materials. The study investigated the optimal doping amount to achieve maximum gasification reactivity under specific conditions for the modified red mud. The steam/carbon ratio for steam reforming was optimized to achieve maximum syngas yield and stability of the oxygen carrier during redox cycling. Compared to raw RM, the modified RM-20CM exhibited increased specific surface area and greater numbers of active sites. A nickel-iron bimetallic synergistic effect enhanced oxygen vacancy concentration within the oxygen carriers, thereby improving oxygen mobility. The stable lattice template enabled the OCs to maintain high OCs activity throughout gasification cycles, while added cobalt-manganese oxide catalyzed light hydrocarbon cracking. Over 10 gasification cycles, RM-20CM sustained consistent syngas yield (1470.5 mL/g), carbon conversion efficiency (82.7 %), and cold gas efficiency (93.8 %).

Conventional carbon electrode fabrication relies on exogenous chemical dopants, bringing extra costs and environmental risks. To address these issues, this work develops a green two-step co-pyrolysis strategy using bamboo and bovine bone to fabricate high-performance porous carbon. Distinct from traditional single-biomass systems requiring chemical doping, bovine bone acts as a natural N/P-containing template and dopant. Its synergistic interaction with bamboo realizes in-situ heteroatom co-doping and hierarchical pore formation, as confirmed by thermogravimetric analysis. The optimized BaBo12 sample delivers a capacitance of 298 F/g at 0.5 A/g, a large surface area of 1152 m2/g, and N/P contents of 2.72% and 0.25%. The symmetric supercapacitor achieves 8.89 Wh/kg energy density at 125 W/kg power density, with 96.97% capacitance retention after 40,000 cycles. The superior electrochemical performance confirms that bovine bone achieves green and efficient pore regulation and heteroatom co-doping during co-pyrolysis. By leveraging the multifunctional characteristics of biomass precursors, this work establishes a fully biomass-derived synthesis framework that eliminates reliance on chemical dopants, providing an innovative strategy for the circular valorization of biomass waste and highperformance carbon electrode preparation.

Designing suitable dual functional materials (DFMs) is one of the most critical issues in the development of biomass sorption enhanced gasification (BSEG) technology. This article systematically investigated the potential of steel slag (SS) as a Ca source for the preparation of DFMs in the BSEG through fixed bed experiments, density functional theory (DFT) calculations and Aspen Plus process simulations. Fixed bed experiments demonstrated that SS-based DFMs could promote H2 production during the BSEG, with the H2 concentration reaching 47.9 vol % and the H2 yield increase of 6.4 times. DFT calculations indicated that the doping of exogenous Ni and the presence of Mg in SS were potential reasons for enhancing the adsorption and catalytic performance of DFMs. The existence of oxygen vacancies (Ov) could significantly increase the binding energy between CO2 and the DFMs surface. Aspen Plus simulations suggested that when using the syngas produced by the BSEG for dimethyl ether (DME) synthesis, attention should be paid to the selectivity of H2 in the syngas by DFMs. This study contributed to the development of BSEG technology and provided new insights for the design and development of efficient DFMs.

Large-scale deployment of anion exchange membrane water electrolysis cells (AEMWE) is constrained by two critical challenges: high replacement costs of catalyst-coated membrane (CCM)-based membrane electrode assemblies (MEA) and severe mass transfer limitations caused by gas blockage in conventional flow fields under high current densities. To address these issues, this study developed a COMSOL simulation method for low-cost catalyst-coated substrate (CCS)-based MEA, replacing the black-box gas diffusion electrode (GDE) module with an independent partitioned boundary framework to simulate catalyst-saving rapid membrane replacement. A gas-liquid separation three-way baffle flow field (TBFF) was proposed and iteratively optimized: initial zoning mitigated gas stagnation; bilaterally symmetric baffles boosted current density by 19.8 % versus conventional flow fields; slit integration upgraded gas exhaust to a diffusion-convection synergistic mode, achieving a 40.1 % current density increase at 2.3 V and maximally delaying concentration polarization. Sensitivity analysis identified optimal operating parameters, and MEA matching tests indicated that the CCS-TBFF system can match or even exceed the performance of high-cost CCM-conventional flow field systems at medium-to-high current densities. Through dual innovations in flow field structure and MEA configuration, this work numerically decouples mass transfer enhancement from material costs, providing a novel design approach for high-efficiency, low-cost next-generation AEMWE.

A central challenge in co-combustion of aged refuse is suppressing the synergistic release of heavy metals and HCl in high-temperature flue gas. To address the limitations of conventional Ca-based additives, three modified Ca-based sorbents doped with Si, B, and P (CA-I, CA-II, CA-III) were developed. Their structural properties were systematically characterized. Removal efficiency for HCl and six heavy metals (Cd, Cr, Zn, Ni, Cu, Pb) was evaluated between 650°C and 950°C, along with an assessment of ecological risk from heavy metals. CA-II exhibited the highest specific surface area, while CA-III showed stable adsorption above 750°C and significantly reduced ecological risk, with Cd and Zn identified as key risk elements. The optimal additive dosage was 5% to avoid agglomeration. This study provides a novel design strategy and fundamental data for synergistic control of pollutants and ecological risk during co-combustion.Implications: This study offers a viable engineering solution for the synergistic control of HCl and heavy metals during waste co-combustion, providing practitioners with a high-efficiency, high-temperature adsorbent (CA-III). From a policy perspective, the technology significantly reduces ecological risks - particularly for Cadmium and Zinc - by stabilizing toxic pollutants, thereby supporting "zero-waste city" initiatives and helping to mitigate public opposition (NIMBY) to incinerators. These findings provide scientific evidence to promote the use of phosphorus-modified additives in solid waste management regulations, facilitating the safe energy recovery of aged landfill refuse and improving the sustainability of waste-to-energy operations.

In the process of biomass chemical looping gasification(BCLG), the interactions between alkali metals and OC are complex and multifaceted. To clarify the mechanisms of these interactions, this study proposes an ex-situ process, where biomass and OC are separately configured. BCLG experiments were conducted in a fixed-bed reactor, and the effects of different alkali metal concentrations and different reaction modes on the gasification process were analyzed. The results indicated that the carbon conversion rate in CLG increased from 66.5 % to 72.9 %, and the gasification efficiency improved from 81.8 % to 85.4 % after the addition of alkali metals. The introduction of alkali metals effectively catalyzes the cleavage of biomass macromolecules and the redox reactions of the oxygen carrier, thereby increasing the yield of products from BCLG. Under the ex-situ mode, the carbon conversion rate of rice husks loaded with 5 % KCl was the highest at 77.5 %, with H2 production and gasification efficiency reaching 614.7 ml/g and 96 %, respectively. After 10 cycles, the gasification efficiency decreased to 88.6 %, which was still higher than that of the initial reaction under the in-situ mode. Moreover, the oxygen carrier's crystal phase and microstructure did not change significantly, demonstrating better reaction performance and cyclic stability.

Biomass-derived carbon materials have found extensive application in supercapacitors and CO2 adsorption, thanks to their unique porosity and tunable surface functionalities, which have enabled sustainable progress and high-value valorization of biomass resources. However, as a typical lignocellulosic biomass, bamboo lacked effective active sites. This study employed soybean meal as a natural heteroatom source to replace chemical reagents. The green and efficient synthesis of the natural heteroatom co-doped bamboo-derived carbon material was achieved through multi-source biomass co-pyrolysis technology. The optimized carbon material (KBSM-8) achieved gravimetric capacitance of 322.10 F/g and volumetric capacitance of 339.57 F/cm3. The SC-KBSM-8 (symmetric supercapacitor) achieved 97.29 % performance stability after 10,000 cycles. Meanwhile, the SC-KBSM-8 exhibited excellent power density (6000 W/kg) and energy density (13.79 Wh/kg). During CO2 adsorption, KBSM-8 demonstrated a CO2 adsorption capacity of 3.754 mmol/g at 25 degrees C, and outstanding cyclic regeneration performance (99.76 % retention rate after 10 reuse cycles). The possible pathways for the formation of heteroatom active sites in porous carbon were elucidated through the analysis of gas and liquid products from the co-pyrolysis of bamboo and soybean meal using TG-MS and Py-GC/MS. In this study, the green and successful doping of heteroatoms was realised by co-pyrolysis of different types of biomass, and the mechanism of heteroatom doping was explored, which offered a valuable reference for the synthesis of heteroatom-doped carbon materials with high-performance and multi-area applications.

Biomass-derived carbon has become an ideal supercapacitor electrode material for its unique pore structure and favorable surface functional group modulation ability, demonstrating growing significance in electrochemistry. Based on this, this work adopted coconut shell as a carbon electrode precursor to fabricate flake-like nitrogen-containing porous carbon electrodes. This is achieved by pyrolysis in a one-pot method using CH3COONH4 as a combined nitrogen source and templating agent, alongside KHCO3 as a green activator, providing an eco-friendly alternative to the conventional KOH method. The templating agent swelled the carbon pore channels during pyrolysis, and the gas stripping overflow further squeezed and ablated the pores, enlarging the pore diameters. At the same time, N atoms replace C atoms and form a large number of active sites for redox reactions in the carbon structure, providing additional charge and thus expanding the capacitance. The best sample exhibited a mass specific capacitance of 302.2 F/g at 0.5 A/g current density in 6 M KOH solution, and the supercapacitor fabricated from this sample had a maximum energy density of 9.19 Wh/kg and a maximum power density of 5,000 W/kg. The supercapacitors maintained 100% Coulombic efficiency and 99.38% capacity retention after 12,000 cycles, which demonstrated the excellent electrochemical performance of the device.

To address the issues of difficult pore structure regulation, high cost, and pollution in traditional porous carbon preparation, this study utilizes poplar wood and yeast as biomass raw materials to prepare porous carbon (PYPACs) via co-pyrolysis combined with the green activator KHCO3. Volatiles released during yeast precarbonization can "stretch" the carbon matrix to form initial pores, and the N and O heteroatoms contained in yeast can construct active sites, guiding KHCO3 etching to form a porous structure. The sample PW1Y1-400 exhibits the optimal comprehensive performance when the mass ratio of poplar wood to yeast is 1:1 and the precarbonization temperature is 400 degrees C. PW1Y1-400 achieves a specific capacitance of 369.7 F/g at 0.5 A/g. The assembled symmetric supercapacitor (PW1Y1-400/SSC) delivers a specific capacitance of 288.35 F/g at 0.25 A/ g. It maintains a capacity retention rate of 98.19 % and a Coulombic efficiency retention rate of 99.94 % after 10000 cycles. At a power density of 75 W/kg, it exhibits an energy density of 12.01 Wh/kg. This method realizes a fully green and pollution-free process, providing a new path for the green production of porous carbon.

Aged refuse (AR), with high combustible content, high lower heating value (dry basis), and low moisture, is well suited for energy recovery. These properties make AR a major feedstock for co-combustion in refuse-to-energy facilities. However, AR poses environmental safety concerns due to its high contents of heavy metals and chlorine, accumulated through long-term landfilling. This study investigated the release of heavy metals (Cd, Cr, Zn, Ni, Cu, Pb, Mn) and HCl during co-combustion of AR and MSW in a tube furnace, aiming for clean co-disposal. The effects of refuse sorting, AR age, blending ratio, temperature, N-2/O-2 ratio, and additives on the release of HCl and heavy metals during combustion were investigated. Results show that Cr and Mn are more volatile in AR. Increased AR age enhances the volatilization of Cd and Cr. Cu and Zn showed the highest release at 30% and 20% AR blending ratios, respectively, and were most affected by temperature. HCl release reached saturation at 950 degrees C. Higher N-2/O-2 ratios increased the release of Ni, Pb, Zn, and Cr but reduced the release of Cd, Mn, Cu, and HCl. The three additives inhibited HCl and most heavy metal release, with overall adsorptivity: CaO > CaCO3 > Ca(OH)(2).

Photovoltaic-electrolyzer direct coupling systems suffer from low energy utilization under non-design conditions due to impedance mismatch. This paper proposes an optimization strategy for photovoltaic-AEM hydrogen production systems based on dynamic reconfiguration of electrolyzer arrays to address issues arising from high photovoltaic variability. A refined AEM electrolyzer and PV model was established, alongside an efficient solution algorithm based on precomputed vectorized scanning. Typical daily meteorological data were extracted using K-medoids clustering, and a hybrid genetic algorithm framework considering maximum current density constraints was constructed to synergistically optimize system capacity and real-time array topology. Simulation results demonstrate that this dynamic reconfiguration strategy significantly enhances system performance: system energy utilization increases from 91.05% to 99.13%, levelized hydrogen production cost (LCOH) decreases by 17.55%, and annual net revenue increases by 15.22%. This study proves the significant advantages of dynamic reconfiguration technology in improving the economic viability and resilience of off-grid green hydrogen systems.

For the process of sorption-enhanced hydrogen-rich syngas production from biomass (SEHB), achieving efficient regeneration of dual-functional materials (DFMs) remains an unresolved challenge. In this study, three different DFMs were synthesized and applied in SEHB. The effects of three regeneration strategies-high-temperature calcination (HTC), coupling with dry reforming of methane (DRM), and coupling with the reverse Boudouard reaction (RB)-on their cyclic performance were systematically compared. The results showed that HTC caused gradual sintering of the DFMs during cycling. The RB route consumed carbon within the DFMs, which led to collapse of the carbon framework. Cyclic tests indicated that both regeneration methods resulted in a significant decline in the cyclic performance of the DFMs. In contrast, the DRM-based regeneration maintained a nearly stable total gas yield over five cycles, with an average total gas yield of 42.6 mmol/gbiomass. This study provided valuable insights into the efficient regeneration of DFMs in the SEHB process.

Anion exchange membrane water electrolysis (AEMWE) systems exhibit nonlinear electrochemical behavior and delayed dynamic response under fluctuating load conditions, which complicate stable and efficient operation. In this study, a nonlinear simulation model of an AEM electrolyzer is established by considering activation, ohmic, and concentration overpotentials, enabling the simulation and analysis of voltage responses under different operating conditions. On this basis, a control-oriented reduced-order prediction model is further developed to describe the dominant dynamic relationship among current response, temperature-dependent ohmic impedance variation, and ohmic overpotential. A model predictive control (MPC)-PID control framework is then constructed to handle operating constraints and improve dynamic performance under load disturbances. The proposed method is evaluated under step-load, continuously varying load, and model-uncertainty conditions, and is compared with conservative PI, aggressive PID, and standalone MPC strategies. The results show that, under step disturbance, the MPC-PID strategy achieves a settling time of 0.552s and a root mean square error of 0.0791A/cm2. Compared with the aggressive PID strategy, the overshoot is reduced from 14.377% to 7.245%, and the constraint violation index decreases from 0.396 to 0.0408. Sensitivity tests further indicate that the proposed strategy maintains stable convergence under ohmic-impedance parameter mismatch, feedback-measurement perturbation, and equivalent thermal disturbance. The study demonstrates that the proposed dynamic modeling and coordinated control approach is effective for improving the operating stability of AEM electrolyzers under variable power input and offers a useful reference for the dynamic operation and control design of renewable-powered hydrogen production systems.

While significant progress has been made in studying multi-heteroatom co-doped carbon materials, considerable challenges remain in thoroughly exploring how various heteroatoms impact their properties. This study synthesized multi-heteroatom co-doped bamboo-derived carbon materials using a simple one-step carbonization process combined with a green heteroatom doping strategy. The effect mechanism of heteroatom types and functional group types on their electrochemical properties was analyzed from micro- and macro-perspectives through experiments and simulations. The best carbon material (KHBS-2) provided excellent heteroatom content (N: 2.44 %, O: 10.19 % and S: 0.58 %). KHBS-2 displayed superior gravimetric capacitance (324.62 +/- 5.70 F/g), volumetric capacitance (336.59 +/- 9.02 F/cm3). Symmetric supercapacitors assembled with KHBS-2 achieved extraordinary cycling stability (99.07 %). At the microscopic scale, typical N-containing active sites (N-5, N-6 and N-Q) significantly enhanced the adsorption of K ions on porous carbon. Moreover, the adsorption of K ions by carbon materials can be significantly enhanced with the simultaneous presence of N-5, N-X and N-Q with C-O. And the C-S functional group could weaken the adsorption effect of N/O functional groups on K ions to a certain extent. On this basis, this study investigated the effects of different types of active sites on the density of states and electrostatic potential of carbon materials.

Reusing valuable metals from used lithium-ion batteries (LIBs) is currently a hot topic in the field of hazardous waste disposal. In this work, the possibility of spent lithium-ion batteries as oxygen carriers was investigated through three treatments of cathode materials at different stages of the recycling process. The results showed that the cathode material possessed abundant lattice oxygen, which substantially contributed to the syngas production. The presence of aluminum foil accelerated the deactivation of the oxygen carrier. The synthesis gas yield of NCM-LA decreased to 693.9 mL/g in the fifth gasification cycle. The prepared de-aluminum material (NCM-L), de-aluminum and de-lithium material (NCM-OA) showed excellent gas production performance with average syngas yields of 961.2 mL/g and 1014.5 mL/g in 15 cycles. NCM-OA had a smaller particle size and possessed the highest lattice oxygen concentration and porosity. After releasing surface lattice oxygen, OCs were reduced to low-valent metals, thereby providing more catalytic sites and enhancing carbon dioxide adsorption. This work proposes a more affordable and eco-friendly approach for the further industrial application of cathode materials for spent lithium-ion batteries.